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41.
旅游者认知地图研究综述 总被引:2,自引:0,他引:2
认知地图是行为地理学中的一个重要研究领域,本文在梳理认知地图的概念体系、地理学与心理学对认知地图研究基础上,综述了近30年国内外旅游者认知地图的研究.研究发现:①旅游者认知地图是具有空间定位功能的、动态的、三维的旅游环境综合表象;②受旅游活动特点和旅游地类型影响的旅游者形成了独特的认知地图类型与空间结构;③旅游者在环境习得速度和过程方面都与一般环境学习存在显著差异;④旅游者认知地图形成过程中的人类影响因素主要表现为游客类型影响因素;⑤旅游领域的研究多采用适合现场情境的方法和技术;⑥旅游者认知地图研究尚处于不成熟阶段,主要表现为研究思想、内容和方法技术等方面的缺陷.最后提出旅游者认知地图几个多学科的重要命题.旅游者认知地图研究对于旅游规划、旅游目的地营销和旅游空间行为研究具有一定理论和实践意义. 相似文献
42.
Individualization of tenure through title registration programmes introduced in many African countries after independence with the promise of security of tenure and increased agricultural productivity has, instead, had the opposite effect. Informal land arrangements continue to emerge as a result of the slow pace of land adjudication (formalization) and updating of land information systems. The trend towards computerization of land information systems has only put focus on already existing formal land tenure arrangements, leaving out the informal social tenure arrangements. As a result, there are now many efforts worldwide motivated by the introduction of the Social Tenure Domain Model (STDM), and freely-available and easy-to-use technology tools to identify, document and map land in support of informal land administration arrangements. Actions are made towards the use of community-generated information to support land administration. Using theories from the interplay between formal and informal institutions, this paper discusses the potential outcomes in adopting Volunteered Geographic Information (VGI) in land administration in Kenya. Two case studies are presented that demonstrate the complementary-accommodating, versus the substitutive-competing approaches. These are then compared with the formal land adjudication process in Kenya. It is established that because of the direct involvement of the national mapping agency in land adjudication where VGI is utilized, the outcome is a case of formal adoption of VGI, while in the other case, where there is little or no involvement by the national mapping agency, the outcome is more of competition and substitution. The latter is an example in which the VGI is used just like any other information to inform policy making, rather than taking it as the authoritative source. We argue that since informality is – and will always be – part and parcel of land administration in many African countries as a result of ingrained social relations and power structures, adopting crowdsourced land information into existing formal land administration systems should consider the particular land administration process, satisfying innate demands and requirements, thus re-engineered to accommodate VGI. 相似文献
43.
Many agricultural practices are negatively impacting the environment and threatening the ecological foundations of the global food system. Therefore, agroecological practices are being proposed as viable and desirable alternatives. Biophysical, economic, social, and political factors, matched with farmers’ psychological attributes, may all be governing the choice of agricultural practices. Public policies can play a significant role as they can stimulate the adoption of innovative farming practices. The main objective of this research was the evaluation of farmers’ motivations for the adoption of agroecological practices in the viticulture sector in the province of Trento, Italy. A specific focus was laid on the influences from the European Common Agricultural Policy (CAP) measures. For the evaluation of farmers’ perceptions of their systems of practices, the Cognitive Mapping Approach for Analysing Actors’ Systems Of Practices (CMASOP) was applied. Based on information collected during in-depth interviews, Individual and Social Cognitive Maps were generated, representing the most frequently adopted agroecological practices and the major drivers of adoption of such practices, as mentioned by farmers. Drivers of adoption were categorized according to the self-determination theory of human motivations. Farmers reported that adoption of agroecological practices was mainly driven by existence of site-specific pedoclimatic conditions, followed with decreasing importance by requirements from wineries, availability of material, appreciation for aesthetics, health concerns, influence from irrigation consortia, and legal requirements, among which a local legislation for integrated pest management based on a CAP measure. Overall, results show that farmers reported to adopt agroecological practices mainly because of autonomous choices rather than coercion. Therefore, wineries and local policy-makers might incentivize the adoption of agroecological practices by promoting autonomy-supportive policies that foster farmers’ identified and intrinsic motivations. 相似文献
44.
For quantitative water management, fine analysis of spatial and temporal interactions between cropping systems and water resources helps identify time and site-specific withdrawal situations. However, it is a methodological challenge to provide fine-resolution analyses at the scale of large watersheds used for crises management. In this study, we present a methodology based on multiple methods and mixed sources of information to finely model an agricultural landscape (AL) that represents the spatial distribution of cropping systems. Our approach is based on progressively hybridizing databases and local actors' and experts' knowledge to produce a spatially explicit and dynamic model. The Land Parcel Identification System database, which resulted from the European Common Agricultural Policy, is crucial for our method since it provides the spatial and temporal basis of our model (i.e., geographic delineation of islets and information about crop sequences). Local knowledge is used to identify factors determining spatial distribution of cropping systems and to build a generic model that simulates farmers' crop-management strategies. The model was qualitatively and quantitatively evaluated using a multi-agent simulation platform (MAELIA). We asked local experts on quantitative water management to evaluate the ability of the platform to reproduce intra- and inter-annual dynamics at different levels when using our model of the AL as input. The experts were satisfied with the results; they validated the predicted dynamics of the variables, and some discussed the objectivity of the values. We discuss the method’s contribution to current challenges in modeling large agricultural areas and the associated tradeoffs. The approach is promising for policy makers who wish to develop integrated, locally adapted land-management strategies. 相似文献
45.
Landscapes provide an array of services to society, from the provision of food and material, to the provision of cultural ecosystem services such as recreation, aesthetics or spirituality. Studies on cultural ecosystem services, however, remain rare and little is known about the spatial localisation of these services. In this study, we adopt and test a framework to identify and map the provision of cultural ecosystem services as perceived by tourists in an Alpine region, i.e. the region of South Tyrol in Italy. A photo-based questionnaire survey is combined with cartographical representations of landscape types to elicit hot and coldspot areas of cultural ecosystem service provision. We statistically test for influences of the land use type and the respondents' socio-demographic background on the tourists' perception of these services. The results show that different spatial patterns emerge for each of the investigated cultural ecosystem services depending on the distribution and extent of the landscape types to which they are related. In particular traditionally managed landscapes, small in extent and mainly scattered over large areas between 1000 and 2200 m a.s.l., are hotspot areas of aesthetic beauty, leisure activities and spirituality. In contrast, intensively managed landscapes, mainly located in the lowland plains of the study site, are considered to be more important for the provision of cultural heritage values. While the results suggest that land use type exerts the strongest influence upon tourists' perception, factors such as the respondents' perceived importance of the services, their gender, cultural background, environmental engagement and experience with the landscape play a significant but subordinate role. We conclude that the spatially explicit information about the provision of cultural ecosystem services can serve as a helpful basis for the design and further implementation of land use policies that acknowledge the high touristic value of traditionally used landscapes in mountain regions. 相似文献
46.
The effectiveness of four grassland-specific agri-environment measures (AEM), implemented in the frame of the European Agricultural Fund for Rural Development (EAFRD) in the period 2007–2013 in Slovenia was studied. We questioned whether the measures – “extensive grassland maintenance”; “preservation of special grassland habitats”; “preservation of grassland habitats for butterflies” and “bird conservation in humid extensive meadows in Natura 2000 sites” did genuinely support the conservation (maintenance or improvement) of high nature value (HNV) grasslands in Slovenia. The HNV grasslands were defined on the basis of national fine-resolution field mapping of habitat types. Two main outcomes emerged: AEM did not reach the vast majority of HNV grasslands in Slovenia (only 3%); the proportion of HNV grassland area included in AEM was negligibly low (1). Moreover, even this very limited interest in AEM did not target only grasslands of HNV, but any permanent grasslands regardless of their conservation value: forty-one percent (41%) of the grassland areas included in the AEM were actually non-HNV grasslands (2). The absence of pre-selection criteria for grasslands along with an absence of monitoring of the effectiveness and efficiency of the measures and low interest in the subsidies among farmers, led to almost complete failure of the AEM to promote and conserve species-rich extensive grasslands in Slovenia between 2007 and 2013. Even with some minor differences, the same concept was maintained for the currently running EAFRD 2014–2020, which raises serious concern. 相似文献
47.
David Clayton 《Revue internationale de statistique》2000,68(1):23-43
The paper reviews recent work on statistical methods for using linkage disequilibrium to locate disease susceptibility genes, given a set of marker genes at known positions in the genome. The paper starts by considering a simple deterministic model for linkage disequilibrium and discusses recent attempts to elaborate it to include the effects of stochastic influences, of drift, by the use of either Writht-Fisher models or by approaches based on the coalescence of the genealogy of the sample of disease chromosomes. Most of this first part of the paper concerns a series of diallelic markers and, in this case, the models so far proposed are hierarchical probability models for multivariate binary data. Likelihoods are intractable and most approaches to linkage disequilibrium mapping amount to marginal models for pairwise associations between individual markers and the disease susceptibility locus. Approaches to evalutation of a full likelihood require Monte Carlo methods in order to integrate over the large number of unknowns. The fact that the initial state of the stochastic process which has led to present-day allele frequencies is unknown is noted and its implications for the hierarchical probability model is discussed. Difficulties and opportunities arising as a result of more polymorphic markers and extended marker haplotypes are indicated. Connections between the hierarchical modelling approach and methods based upon identity by descent and haplotype sharing by seemingly unrelated case are explored. Finally problems resulting from unknown modes of inheritance, incomplete penetrance, and phenocopies are briefly reviewed. 相似文献
48.
针对工程制图的课程特点,简要介绍在建构主义教育理念的基础上,进行的零部件拆装实践教学。在教学内容上,给定真实的拆装与测绘环境,用逆向设计模式,画出相应的零部件装配图和零件图。教学手段上加强了数字化教学资源的建设。教学方法上,更注重于以项目为载体,理论教学与实践教学相结合。 相似文献
49.
Recent advances in science mapping allowed to analyze the entire intellectual structure of blockchain and cryptocurrencies in business-related disciplines to identify 174 academic articles as well as 1482 practitioner-oriented articles published since the inception of cryptocurrencies in 2008 to highlight key trends of the published outputs. The results demonstrate academic research done by 389 authors in 296 organizations based in 50 countries that only just initiated the conversation on four major streams of the literature—Bitcoin and cryptocurrencies; blockchain adoption; cryptocurrency and blockchain environment; and business model innovations. When comparing academic scholarship to practitioner-oriented literature, the results demonstrate that practitioners discussed investor-related themes, cryptocurrency intrinsic value, political-economic sphere, and the impact of cryptocurrency and blockchain technologies on the wider society in greater detail. As a result, a number of themes are identified and discussed that could align academic and practitioner interests and provide guidance for further research in this important field. 相似文献
50.
This article provides a comprehensive review of scholarly research on credit risk measurement during the last 57 years applying bibliometric citation analysis and elaborates an agenda for future research. The bibliography is compiled using the Institute for Scientific Information (ISI) Web of Science (WOS) database and includes all articles with citations over the period 1960–2016. Specifically, the review is carried out using 1695 articles across 72 countries published in 442 journals by 2928 authors. The findings suggest that credit risk research is multifaceted and can be classified into six streams: (1) defaultable security pricing, (2) default intensity modeling, (3) comparative analysis of credit models, (4) comparative analysis of credit markets, (5) credit default swap (CDS) pricing, and (6) loan loss provisions. The article contributes through synthesizing and identifying existing as well as emerging research streams. 相似文献